construction of materials disbursal shed for 36-santirbazar (s/t) assembly constituency under santirbazar sub-division-providing and laying in position cement concrete of specified grade excluding the cost of centering and shuttering - all work upto plinth level. 1:2:4 (1 cement:2 fine sand:4 graded well burnt brick aggregate 20 mm nominal size) 2 providing steel work in built up tubular trusses including cutting, hoisting, fixing in position and applying a priming coat of approved steel primer, welded and bolted including special shaped washers etc. complete as required : 3 supply & installation of pre-painted galvalume sheets for roofing/cladding (size, shape and pitch of corrugation as approved by engineer-in-charge) in 550mpa steel grade, made out of cold rolled steel coated with zinc-aluminium alloy coating of 43.5% zn,55% al and 1.5% silicon confirming to astm a792/a792m and as1397, alloy coating az150/az70, colour coated with high quality polyester coating, top coated of modified polyester of 20 micron, back side coat of 5 micron, having epoxy primer coat of 5 micron on both side. sheet should have protective guard film of 25 microns minimum to avoid scratches while transportation and should be supplied in single length upto 12 metre or as desired by engineer-incharge. the sheet shall be fixed using self drilling /self tapping screws of size (5.5x 55mm) with epdm washers filled with white lead complete upto any pitch in horizontal/ vertical or curved surfaces excluding the cost of purlins, rafters and trusses and including cutting to size and shape wherever required and as per direction of engineer-in-charge. 4 supply & installation of pre-painted galvalume sheets roofing accessories in 550mpa steel steel grade, made out of cold rolled steel coated with zinc-aluminium alloy coating of 43.5% zn, 55% al and 1.5% silicon confirming to aastm a792/a792m and as1397, alloy coating az150/az70, colour coated with high quality polyester coating, top coated of modified polyester of 20 micron, back side coat of 5 micron, having epoxy primer coat of 5 micron on both side etc. complete as per direction of engineer-in-charge. sheet should have protective guard film of 25 microns minimum to avoid scratches while transportation. sheet should have protective guard film of 25 microns minimum to avoid scratches while transportation. the sheet shall be fixed using self drilling /self tapping screwswith epdm washers complete for ridges/valley/gutter/flashing of width 610mm: